In order to illuminate a liquid crystal display panel etc., a back light has been used, in which light-emitting devices are arranged in lines along side surfaces of a light guiding plate. In addition, when irradiating a large-size display section of, e.g., a liquid crystal television with light from a back side, a back light has been known, in which a plurality of light-emitting devices are arranged in matrix on a large-size wiring substrate.
As light-emitting devices used for a large-size back light, a light-emitting device provided by combining a light-emitting element which is a point light source with a luminous flux control member (light guiding member) has been known (see, e.g., Patent Document 1). The light guiding member has, e.g., an approximately rounded quadrangular planar shape, and a hemispherical hollow is formed around a light emission center of the light-emitting element. A first light exit surface portion defining a smoothly-curved surface which downwardly protrudes at the center of a light exit surface, and a second light exit surface portion continuously formed so as to surround the first light exit surface portion, and defining a smoothly-curved surface which upwardly protrudes are formed on an outer surface side as an emission control surface.
In a surface light-emitting apparatus in which such light-emitting devices are arranged in matrix, each of the light-emitting devices can continuously diffuse light from the light-emitting element within a desired area to be irradiated, thereby obtaining illumination light with uniform luminance.